Patent Literature (PTL) 1 discloses a disk drive device which includes a device body equipped with a storage portion, a cover body, a rotational urging spring, a lock mechanism, and an unlock mechanism. The cover body is turnably supported on the device body via a shaft body corresponding to a support shaft, and is turnable from a cover opening position to a cover closing position. The rotational urging spring accumulates rotational urging force for turning the cover body from the cover closing position to the cover opening position of the cover body during turning of the cover body from the cover opening position to the cover closing position. The lock mechanism includes engaging portions disposed nearer the shaft body and nearer the device body, and limits turning of the cover body by engagement of the engaging portions. The unlock mechanism shifts the engaging portions disposed nearer the shaft body and nearer the device body relative to each other to allow rotation of the cover body by the rotational force of the rotational urging spring. This disk drive device rotates the cover body in a plane parallel with a disk to facilitate attachment and detachment of the disk.